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The Anti-Tracker

The AntiTracker is a new concept in GPS tracking systems. The idea behind the AntiTracker is that many units in the field do not need to have their positions reported back. These field units are however interested in where the units being tracked are located.

Think of marathon race. The first and last runners in the race are being tracked thanks to trackers on vehicles following the race. Each of the checkpoints is stationary, but they want to know when the first runner will be reaching them, and how long it will be until the final runner passes them.

This allows significant cost savings in terms of not only equipment capital costs, but also in terms of operational costs including licenses and batteries.
With this in mind, Radioactive Networks has just produced what we are calling the 'Anti-Tracker'. Rather than develop the display interface, we have decided to use a commercially available interface - a simple GPS reciever.

Two Models

Initially, Radioactive Networks will be releasing two versions of the AntiTracker. They will be :-

Basic - The ability to display positions on a GPS receiver with NMEA input - meaning that it will not work with the entry level Garmin eTrex. The design also uses two embedded processors, rather than a single integrated processor.

Pro - The Pro version of the AntiTracker contains all the capabilities of the Basic unit, except it will upload to GARMIN GPS receivers in BINARY format, meaning that it will work with the basic Garmin eTrex. An upgrade will include the capability for ICONs to be also uploaded to the GARMIN.

The AntiTracker BASIC

is designed so that the HAM RADIO community can recieve the benefits of the AntiTracker without having to go for the expense of the PRO model. This device will not upload positions in GARMIN Binary mode, nor will it upload any symbols assigned to objects. In fact, Symbols may even change every time a new position update is received.
One of the areas that most tracking systems concentrate on is acquiring GPS positions and getting them back into a central location. Some even send the positions back to the GPS tracking units. http://www.radio-active.net.au/web/tracking/atbasicv1.jpg
What has not been done is create a distributed system in the field, reporting the positions without being tracked themselves. This allows significant cost savings in terms of not only equipment capital costs, but also in terms of operational costs including licenses and batteries.
With this in mind, Radioactive Networks has just produced what we are calling the 'Anti-Tracker'. Rather than develop the display interface, we have decided to use a commercially available interface - a simple GPS reciever.

Basically any GPS that understands the GPWPL NMEA sentance will work. This includes many Magellan GPS receivers too.
The GARMIN Etrex BASE MODEL WILL NOT WORK. Neither will Garmin GPS-V or the Garmin Street Pilot (First Version).
The position of all the users being tracked appears on the GPS receiever along with any roads and other features programmed into the device. Then when the person being tracked moves, the icon on the GPS will move too.

Implemented Packets

For the technically minded, we will now include information on the packets that this device will decode -
- Standard Position Reports
- Standard Position Reports with Timestamps
- MIC-E Position Reports
- MIC-E Position Reports with Timestamps
- Standard Object Reports
- Standard Item Reports

Building the AntiTracker BASIC

Our prototype is only about 2" x 3" making it quite portable. No circiuit board is available at this stage. This design uses four inexpensive IC's. The components we are using include a couple of PIC16F628's, MX614 and MAX232. None of these parts are expensive, and are available surface mount.

You will need to contact us for programned IC's or the HEX file to program your own. Please note that there are two pages to this circuit diagram. GIMP for instance will not read the second page. Kodak Imaging supplied with many versions of the Windows Operating System will work correctly

The AntiTracker PRO

...(still in development)

One of the areas that most tracking systems concentrate on is acquiring GPS positions and getting them back into a central location. Some even send the positions back to the GPS tracking units.
What has not been done is create a distributed system in the field reporting the positions without being tracked themselves. This allows significant cost savings in terms of not only equipment capital costs, but also in terms of operational costs including licenses and batteries.
With this in mind, Radioactive Networks have just produced what we are calling the 'Anti-Tracker'. Rather than develop the display interface, we have decided to use a commercially available interface - a simple GPS receiver.. http://www.radio-active.net.au/web/tracking/anti-pro1.jpg

The PRO version of this device can use eithe the $WPGPL sentences understood by many GPS receievers that allow NMEA uploading, or GARMIN BINARY format understood by the newer Garmin eTREX GPS receivers. This version is based on the PIC16F876 processor with an MX614 modem IC. The code is getting close to totally filling the memory of the processor. During testing we also discovered that the CPU clock needed to be doubled in order to process the data in the available time.
The position of all the users being tracked appears on the GPS receiever allong with any roads and other features programmed into the device. Then when the person being tracked moves, the icon on the GPS will move too.

Progress**

This project is getting close to completion - at least on the firmware side. We are now decoding normal and third party packets and displaying them on the GPS receiver in GARMIN and TEXT modes. At present packets are not being correctly decoded when one packet follows within 100 mSec of the previous packet being completed. Although rare in object tracking, it is quite common in iGate operations.

Since GARMIN and NMEA operate at different speeds, we are also going to make the selection of the mode switchable. This needs to be implemented. The GARMIN protocol has the ability to set ICONs and we also hope to implement this.

For the technically minded, we will now include information on the packets that this device will decode -
- Standard Position Reports
- Standard Position Reports with Timestamps
- MIC-E Position Reports
- MIC-E Position Reports with Timestamps
- Standard Object Reports
- Standard Item Reports